/**
 * Copyright (c) 2006-2015, JGraph Ltd
 * Copyright (c) 2006-2015, Gaudenz Alder
 */
/**
 * Class: mxStackLayout
 *
 * Extends <mxGraphLayout> to create a horizontal or vertical stack of the
 * child vertices. The children do not need to be connected for this layout
 * to work.
 *
 * Example:
 *
 * (code)
 * var layout = new mxStackLayout(graph, true);
 * layout.execute(graph.getDefaultParent());
 * (end)
 *
 * Constructor: mxStackLayout
 *
 * Constructs a new stack layout layout for the specified graph,
 * spacing, orientation and offset.
 */
function mxStackLayout(graph, horizontal, spacing, x0, y0, border)
{
    mxGraphLayout.call(this, graph);
    this.horizontal = (horizontal != null) ? horizontal : true;
    this.spacing = (spacing != null) ? spacing : 0;
    this.x0 = (x0 != null) ? x0 : 0;
    this.y0 = (y0 != null) ? y0 : 0;
    this.border = (border != null) ? border : 0;
};

/**
 * Extends mxGraphLayout.
 */
mxStackLayout.prototype = new mxGraphLayout();
mxStackLayout.prototype.constructor = mxStackLayout;

/**
 * Variable: horizontal
 *
 * Specifies the orientation of the layout. Default is true.
 */
mxStackLayout.prototype.horizontal = null;

/**
 * Variable: spacing
 *
 * Specifies the spacing between the cells. Default is 0.
 */
mxStackLayout.prototype.spacing = null;

/**
 * Variable: x0
 *
 * Specifies the horizontal origin of the layout. Default is 0.
 */
mxStackLayout.prototype.x0 = null;

/**
 * Variable: y0
 *
 * Specifies the vertical origin of the layout. Default is 0.
 */
mxStackLayout.prototype.y0 = null;

/**
 * Variable: border
 *
 * Border to be added if fill is true. Default is 0.
 */
mxStackLayout.prototype.border = 0;

/**
 * Variable: marginTop
 *
 * Top margin for the child area. Default is 0.
 */
mxStackLayout.prototype.marginTop = 0;

/**
 * Variable: marginLeft
 *
 * Top margin for the child area. Default is 0.
 */
mxStackLayout.prototype.marginLeft = 0;

/**
 * Variable: marginRight
 *
 * Top margin for the child area. Default is 0.
 */
mxStackLayout.prototype.marginRight = 0;

/**
 * Variable: marginBottom
 *
 * Top margin for the child area. Default is 0.
 */
mxStackLayout.prototype.marginBottom = 0;

/**
 * Variable: keepFirstLocation
 *
 * Boolean indicating if the location of the first cell should be
 * kept, that is, it will not be moved to x0 or y0. Default is false.
 */
mxStackLayout.prototype.keepFirstLocation = false;

/**
 * Variable: fill
 *
 * Boolean indicating if dimension should be changed to fill out the parent
 * cell. Default is false.
 */
mxStackLayout.prototype.fill = false;

/**
 * Variable: resizeParent
 *
 * If the parent should be resized to match the width/height of the
 * stack. Default is false.
 */
mxStackLayout.prototype.resizeParent = false;

/**
 * Variable: resizeParentMax
 *
 * Use maximum of existing value and new value for resize of parent.
 * Default is false.
 */
mxStackLayout.prototype.resizeParentMax = false;

/**
 * Variable: resizeLast
 *
 * If the last element should be resized to fill out the parent. Default is
 * false. If <resizeParent> is true then this is ignored.
 */
mxStackLayout.prototype.resizeLast = false;

/**
 * Variable: wrap
 *
 * Value at which a new column or row should be created. Default is null.
 */
mxStackLayout.prototype.wrap = null;

/**
 * Variable: borderCollapse
 *
 * If the strokeWidth should be ignored. Default is true.
 */
mxStackLayout.prototype.borderCollapse = true;

/**
 * Variable: allowGaps
 *
 * If gaps should be allowed in the stack. Default is false.
 */
mxStackLayout.prototype.allowGaps = false;

/**
 * Variable: gridSize
 *
 * Grid size for alignment of position and size. Default is 0.
 */
mxStackLayout.prototype.gridSize = 0;

/**
 * Function: isHorizontal
 *
 * Returns <horizontal>.
 */
mxStackLayout.prototype.isHorizontal = function()
{
    return this.horizontal;
};

/**
 * Function: moveCell
 *
 * Implements <mxGraphLayout.moveCell>.
 */
mxStackLayout.prototype.moveCell = function(cell, x, y)
{
    var model = this.graph.getModel();
    var parent = model.getParent(cell);
    var horizontal = this.isHorizontal();

    if (cell != null && parent != null)
    {
        var i = 0;
        var last = 0;
        var childCount = model.getChildCount(parent);
        var value = (horizontal) ? x : y;
        var pstate = this.graph.getView().getState(parent);

        if (pstate != null)
        {
            value -= (horizontal) ? pstate.x : pstate.y;
        }

        value /= this.graph.view.scale;

        for (i = 0; i < childCount; i++)
        {
            var child = model.getChildAt(parent, i);

            if (child != cell)
            {
                var bounds = model.getGeometry(child);

                if (bounds != null)
                {
                    var tmp = (horizontal) ?
                        bounds.x + bounds.width / 2 :
                        bounds.y + bounds.height / 2;

                    if (last <= value && tmp > value)
                    {
                        break;
                    }

                    last = tmp;
                }
            }
        }

        // Changes child order in parent
        var idx = parent.getIndex(cell);
        idx = Math.max(0, i - ((i > idx) ? 1 : 0));

        model.add(parent, cell, idx);
    }
};

/**
 * Function: getParentSize
 *
 * Returns the size for the parent container or the size of the graph
 * container if the parent is a layer or the root of the model.
 */
mxStackLayout.prototype.getParentSize = function(parent)
{
    var model = this.graph.getModel();
    var pgeo = model.getGeometry(parent);

    // Handles special case where the parent is either a layer with no
    // geometry or the current root of the view in which case the size
    // of the graph's container will be used.
    if (this.graph.container != null && ((pgeo == null &&
        model.isLayer(parent)) || parent == this.graph.getView().currentRoot))
    {
        var width = this.graph.container.offsetWidth - 1;
        var height = this.graph.container.offsetHeight - 1;
        pgeo = new mxRectangle(0, 0, width, height);
    }

    return pgeo;
};

/**
 * Function: getLayoutCells
 *
 * Returns the cells to be layouted.
 */
mxStackLayout.prototype.getLayoutCells = function(parent)
{
    var model = this.graph.getModel();
    var childCount = model.getChildCount(parent);
    var cells = [];

    for (var i = 0; i < childCount; i++)
    {
        var child = model.getChildAt(parent, i);

        if (!this.isVertexIgnored(child) && this.isVertexMovable(child))
        {
            cells.push(child);
        }
    }

    if (this.allowGaps)
    {
        cells.sort(mxUtils.bind(this, function(c1, c2)
        {
            var geo1 = this.graph.getCellGeometry(c1);
            var geo2 = this.graph.getCellGeometry(c2);

            return (geo1.y == geo2.y) ? 0 : ((geo1.y > geo2.y > 0) ? 1 : -1);
        }));
    }

    return cells;
};

/**
 * Function: snap
 *
 * Snaps the given value to the grid size.
 */
mxStackLayout.prototype.snap = function(value)
{
    if (this.gridSize != null && this.gridSize > 0)
    {
        value = Math.max(value, this.gridSize);

        if (value / this.gridSize > 1)
        {
            var mod = value % this.gridSize;
            value += mod > this.gridSize / 2 ? (this.gridSize - mod) : -mod;
        }
    }

    return value;
};

/**
 * Function: execute
 *
 * Implements <mxGraphLayout.execute>.
 *
 * Only children where <isVertexIgnored> returns false are taken into
 * account.
 */
mxStackLayout.prototype.execute = function(parent)
{
    if (parent != null)
    {
        var pgeo = this.getParentSize(parent);
        var horizontal = this.isHorizontal();
        var model = this.graph.getModel();
        var fillValue = null;

        if (pgeo != null)
        {
            fillValue = (horizontal) ? pgeo.height - this.marginTop - this.marginBottom :
                pgeo.width - this.marginLeft - this.marginRight;
        }

        fillValue -= 2 * this.border;
        var x0 = this.x0 + this.border + this.marginLeft;
        var y0 = this.y0 + this.border + this.marginTop;

        // Handles swimlane start size
        if (this.graph.isSwimlane(parent))
        {
            // Uses computed style to get latest
            var style = this.graph.getCellStyle(parent);
            var start = mxUtils.getNumber(style, mxConstants.STYLE_STARTSIZE, mxConstants.DEFAULT_STARTSIZE);
            var horz = mxUtils.getValue(style, mxConstants.STYLE_HORIZONTAL, true) == 1;

            if (pgeo != null)
            {
                if (horz)
                {
                    start = Math.min(start, pgeo.height);
                }
                else
                {
                    start = Math.min(start, pgeo.width);
                }
            }

            if (horizontal == horz)
            {
                fillValue -= start;
            }

            if (horz)
            {
                y0 += start;
            }
            else
            {
                x0 += start;
            }
        }

        model.beginUpdate();
        try
        {
            var tmp = 0;
            var last = null;
            var lastValue = 0;
            var lastChild = null;
            var cells = this.getLayoutCells(parent);

            for (var i = 0; i < cells.length; i++)
            {
                var child = cells[i];
                var geo = model.getGeometry(child);

                if (geo != null)
                {
                    geo = geo.clone();

                    if (this.wrap != null && last != null)
                    {
                        if ((horizontal && last.x + last.width +
                            geo.width + 2 * this.spacing > this.wrap) ||
                            (!horizontal && last.y + last.height +
                                geo.height + 2 * this.spacing > this.wrap))
                        {
                            last = null;

                            if (horizontal)
                            {
                                y0 += tmp + this.spacing;
                            }
                            else
                            {
                                x0 += tmp + this.spacing;
                            }

                            tmp = 0;
                        }
                    }

                    tmp = Math.max(tmp, (horizontal) ? geo.height : geo.width);
                    var sw = 0;

                    if (!this.borderCollapse)
                    {
                        var childStyle = this.graph.getCellStyle(child);
                        sw = mxUtils.getNumber(childStyle, mxConstants.STYLE_STROKEWIDTH, 1);
                    }

                    if (last != null)
                    {
                        var temp = lastValue + this.spacing + Math.floor(sw / 2);

                        if (horizontal)
                        {
                            geo.x = this.snap(((this.allowGaps) ? Math.max(temp, geo.x) :
                                temp) - this.marginLeft) + this.marginLeft;
                        }
                        else
                        {
                            geo.y = this.snap(((this.allowGaps) ? Math.max(temp, geo.y) :
                                temp) - this.marginTop) + this.marginTop;
                        }
                    }
                    else if (!this.keepFirstLocation)
                    {
                        if (horizontal)
                        {
                            geo.x = (this.allowGaps && geo.x > x0) ? Math.max(this.snap(geo.x -
                                this.marginLeft) + this.marginLeft, x0) : x0;
                        }
                        else
                        {
                            geo.y = (this.allowGaps && geo.y > y0) ? Math.max(this.snap(geo.y -
                                this.marginTop) + this.marginTop, y0) : y0;
                        }
                    }

                    if (horizontal)
                    {
                        geo.y = y0;
                    }
                    else
                    {
                        geo.x = x0;
                    }

                    if (this.fill && fillValue != null)
                    {
                        if (horizontal)
                        {
                            geo.height = fillValue;
                        }
                        else
                        {
                            geo.width = fillValue;
                        }
                    }

                    if (horizontal)
                    {
                        geo.width = this.snap(geo.width);
                    }
                    else
                    {
                        geo.height = this.snap(geo.height);
                    }

                    this.setChildGeometry(child, geo);
                    lastChild = child;
                    last = geo;

                    if (horizontal)
                    {
                        lastValue = last.x + last.width + Math.floor(sw / 2);
                    }
                    else
                    {
                        lastValue = last.y + last.height + Math.floor(sw / 2);
                    }
                }
            }

            if (this.resizeParent && pgeo != null && last != null && !this.graph.isCellCollapsed(parent))
            {
                this.updateParentGeometry(parent, pgeo, last);
            }
            else if (this.resizeLast && pgeo != null && last != null && lastChild != null)
            {
                if (horizontal)
                {
                    last.width = pgeo.width - last.x - this.spacing - this.marginRight - this.marginLeft;
                }
                else
                {
                    last.height = pgeo.height - last.y - this.spacing - this.marginBottom;
                }

                this.setChildGeometry(lastChild, last);
            }
        }
        finally
        {
            model.endUpdate();
        }
    }
};

/**
 * Function: execute
 *
 * Implements <mxGraphLayout.execute>.
 *
 * Only children where <isVertexIgnored> returns false are taken into
 * account.
 */
mxStackLayout.prototype.setChildGeometry = function(child, geo)
{
    var geo2 = this.graph.getCellGeometry(child);

    if (geo2 == null || geo.x != geo2.x || geo.y != geo2.y ||
        geo.width != geo2.width || geo.height != geo2.height)
    {
        this.graph.getModel().setGeometry(child, geo);
    }
};

/**
 * Function: execute
 *
 * Implements <mxGraphLayout.execute>.
 *
 * Only children where <isVertexIgnored> returns false are taken into
 * account.
 */
mxStackLayout.prototype.updateParentGeometry = function(parent, pgeo, last)
{
    var horizontal = this.isHorizontal();
    var model = this.graph.getModel();

    var pgeo2 = pgeo.clone();

    if (horizontal)
    {
        var tmp = last.x + last.width + this.marginRight + this.border;

        if (this.resizeParentMax)
        {
            pgeo2.width = Math.max(pgeo2.width, tmp);
        }
        else
        {
            pgeo2.width = tmp;
        }
    }
    else
    {
        var tmp = last.y + last.height + this.marginBottom + this.border;

        if (this.resizeParentMax)
        {
            pgeo2.height = Math.max(pgeo2.height, tmp);
        }
        else
        {
            pgeo2.height = tmp;
        }
    }

    if (pgeo.x != pgeo2.x || pgeo.y != pgeo2.y ||
        pgeo.width != pgeo2.width || pgeo.height != pgeo2.height)
    {
        model.setGeometry(parent, pgeo2);
    }
};
